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Magic Roundabout (Swindon)

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Re: Magic Roundabout (Swindon)

#131

Post by twic »

laumars wrote: post #5
kaffeemitsahne wrote: post #2

Imagine coming from mainland europe and having to drive on the other side of the road (thus also taking roundabouts the other way round), and then navigating this baby...

The beauty of these kind of junctions is you can drive clockwise or anti-clockwise. Essentially it's not a roundabout but rather one junction comprised of lots of roundabouts. The Colchester equivalent better demonstrates this: https://en.wikipedia.org/wiki/Magic_Roundabout_(Colchester) Personal anecdote: I had to drive around one of these junctions during my driving test

The article explains why the Colchester one is particularly cursed: it's built on a native burial ground!

Re: Magic Roundabout (Swindon)

#132

Post by twic »

laumars wrote: post #5
kaffeemitsahne wrote: post #2

Imagine coming from mainland europe and having to drive on the other side of the road (thus also taking roundabouts the other way round), and then navigating this baby...

The beauty of these kind of junctions is you can drive clockwise or anti-clockwise. Essentially it's not a roundabout but rather one junction comprised of lots of roundabouts. The Colchester equivalent better demonstrates this: https://en.wikipedia.org/wiki/Magic_Roundabout_(Colchester) Personal anecdote: I had to drive around one of these junctions during my driving test

In other Colchester roundabout news, the one at North Station is fun - it's a normal roundabout, but with a road cutting right through the middle of it too:

https://www.youhaventlived.com/qblog/2005/QBlog160705A.html

There are lights to make sure nobody crashes - effectively switching it between being a roundabout and being a through road - but it's still pretty weird.

Re: Magic Roundabout (Swindon)

#133

Post by swarnie_ »

njb311 wrote: post #121

I lived in Swindon for 2 years and while drivers can find different things challenging, I would venture to say that it's a lot more straightforward when you're on it than you might imagine. It separates traffic effectively at peak times according to which roads they enter/leave, and as many have mentioned it slows cars down so you aren't pressured to make snap decisions either if you aren't sure. If all else fails, y…

I grew up in Swindon and took my driving test there. The only complication usually is drivers who don't know ho to use it / are timid.

Also the football ground on the corner doesn't help when 1000s of people all arrive at those lights at the same time it can cause chaos.

Re: Magic Roundabout (Swindon)

#134

Post by twic »

Sean1708 wrote: post #14
kaffeemitsahne wrote: post #2

Imagine coming from mainland europe and having to drive on the other side of the road (thus also taking roundabouts the other way round), and then navigating this baby...

I strongly believe that the biggest reason people struggle with the Magic Roundabout is because it's called a roundabout, when it's actually just a collection of 5 roundabouts. If you tackle it one roundabout at a time it's actually not that bad at all, it could be much much better , but it's not bad .

Exactly, it's just a very small gyratory system.

Re: Magic Roundabout (Swindon)

#135

Post by caconym_ »

ken wrote: post #78
snowwrestler wrote: post #61

> however, the roundabout provides a better throughput of traffic than other designs and has an excellent safety record, since traffic moves too slowly to do serious damage in the event of a collision. In 2010, the National Cooperative Highway Research Program concluded that the roundabout reduces injurious crashes by three quarters. One of the hardest things in local democracy is that the best traffic patterns are o…

The problem, as always, is that parties disagree on what "best" means. Governments and safety organizations are pushing for "Vision Zero", i.e., safety at any cost. (My economics professor once pointed out that if you really want zero traffic deaths, just limit all cars to 5 mph everywhere.) For people driving on the road, the current level of risk (roughly 1 death per 100M miles) is acceptable, and arriving quickly…

True, but in this case (apparently) there is the added wrinkle that this roundabout has better throughput than other designs, so what’s the downside? I guess it forces people to think harder than they’d normally have to while driving?

I definitely find myself taking slightly longer routes that let me avoid stressful situations, e.g. turning left onto a busy road.

Re: Magic Roundabout (Swindon)

#136

Post by clarry »

twodave wrote: post #97

A valuable thing to remember about roundabouts is that they are generally meant to slow down traffic in areas of high pedestrian activity and are, above all else, a safety mechanism.

There are roundabouts in places with no pedestrians at all.

Re: Magic Roundabout (Swindon)

#137

Post by TheOtherHobbes »

superhuzza wrote: post #106
vanderZwan wrote: post #98

Earlier quoted context omitted.

I wouldn't be surprised if it is safe partially because people think it's a nightmare to navigate

That's pretty much what the Wikipedia article claims, the roundabout has an "excellent safety record, since traffic moves too slowly to do serious damage in the event of a collision"

I used to drive over it occasionally. It was always decorated with broken glass from a collision.

It's true it has a good safety record if you consider fatalities/injuries. But that's because it's impossible to cross it at speed unless it's completely empty.

I suspect its record for minor collision damage is less reassuring.

The fundamental problem is situational awareness. On a normal roundabout you only have to look in one direction. On the magic roundabout you have to be aware of traffic from the left, right, and front - and if you're not a regular user, you have to do this while trying to navigate the design.

Re: Magic Roundabout (Swindon)

#138

Post by jiveturkey »

mcv wrote: post #43

A better solution for high traffic flow is the turbo roundabout[0] which is getting increasingly popular in Netherland. Before you enter the roundabout, you select the lane for the direction you want to go. You only cross traffic when entering the roundabout for the first time. After that, you simply follow your lane and it delivery you where you want to go. It looks complicated from above, but it's very simple once…

I don't like it. From the bottom, if you want to go straight you enter on the right lane. From the right, if you want to go straight you enter on the left lane. This lack of symmetry means you need to be very familiar with the path in advance, and not get confused about which orientation you're in. For the signage to be far enough from the roundabout to get your bearings in time, it will be too far for most people to even be looking for it. This design will add to the late merge asshole problem.

Re: Magic Roundabout (Swindon)

#139

Post by clarry »

Vaanir wrote: post #42
smcl wrote: post #21

Earlier quoted context omitted.

It’s not easy to understand why it is structured this way. As a local do you have any idea why it’s composed of five mini roundabouts instead of just a single one? Does it feel like it handles high levels of traffic better?

I'm not sure on the actual design decision reasonings, however you can reach many of the exit junctions with multiple routes. So if everyone drove around it sensibly, there _would_ be fewer cars stuck in traffic.

I'd have to see a study or simulation. I can't take it on faith, because what I see is very many points where cars have to stop and yield. Multiple routes could just imply packing more cars into one ginormous intersection where they block each other trying to get in or out. And where you have multiple routes to one junction, you have merging.

Re: Magic Roundabout (Swindon)

#140

Post by tzs »

mcv wrote: post #43

A better solution for high traffic flow is the turbo roundabout[0] which is getting increasingly popular in Netherland. Before you enter the roundabout, you select the lane for the direction you want to go. You only cross traffic when entering the roundabout for the first time. After that, you simply follow your lane and it delivery you where you want to go. It looks complicated from above, but it's very simple once…

> There's no possibility to keep going around until you figure out where you want to go.

I assume that traffic on the loops always has the right of way over traffic trying to enter the loops?

In that case, why can't you keep going around? At the place where the northbound inner loop becomes the southbound outer loop, it crosses the start of the southbound inner loop. The cars coming from the south trying to enter the southbound inner loop have to yield to the cars on the northbound loop, so it should be perfect safe for those cars to turn onto the southbound inner loop.

Note that allowing this maneuver is necessary if you want to allow eastbound or westbound travelers to make U-turns. If it is not allowed, then only northbound or southbound travelers can make a U-turn on this.

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